管理信息系统建设探讨

本文通过分析建设过程中存在的一些矛盾,以信息工程建设应以管理为出发点、并为管理服务为立足点,综合考察一些典型方法的思路、原理、方法,在此基础上提出“分离期法”,尝试解决管理相对稳定和技术飞速发展之间的冲突。

医院信息系统建设探讨

本文通过描述医院信息化建设的基本情况 ,分析建设过程中存在的一些矛盾 ,探讨在医院信息系统开发和推广应用过程中存在的问题 ,及解决的方法和思路。以信息工程建设应以管理为出发点、并为管理服务为立足点 ,综合考察一些典型开发方法的原理、思路 ,在此基础上提出“分离期法”,尝试解决管理相对稳定和技术飞速发展之间的冲突。

Maximum Likelihood Blind Separation of Convolutively Mixed Discrete Sources

In this paper,a Maximum Likelihood(ML) approach,implemented by Expectation-Maximization(EM) algorithm,is proposed to blind separation of convolutively mixed discrete sources.In order to carry out the expectation procedure of the EM algorithm with a less computational load,the algorithm named Iterative Maximum Likelihood algorithm(IML) is proposed to calculate the likelihood and recover the source signals.An important feature of the ML approach is that it has robust performance in noise environments by treating the covariance matrix of the additive Gaussian noise as a parameter.Another striking feature of the ML approach is that it is possible to separate more sources than sensors by exploiting the finite alphabet property of the sources.Simulation results show that the proposed ML approach works well either in determined mixtures or underdetermined mixtures.Furthermore,the performance of the proposed ML algorithm is close to the performance with perfect knowledge of the channel filters.